Description: Small much-branched annual to perennial herbs.
Leaves linear to subulate, margins ciliate; stipules absent.
Flowers terminal or axillary, sessile or pedicellate, solitary, paired or in dense clusters. Calyx lobes mostly 5, erect or spreading; calyx tube becoming hard and swollen and enclosing the fruit. Petals absent. Stamens 1–10, staminodes occasionally present. Ovary 1-locular; styles and stigmas 2.
Fruit usually a 1-seeded indehiscent nutlet, falling enclosed by persistent enlarged calyx.
Distribution and occurrence: World: 12 species, Europe, Asia, Africa, Australia, New Zealand. Australia: 10 species (9 species native, 1 species naturalized), Qld, N.S.W., Vic., Tas., S.A.
Cushion and mat-forming species occasionally cultivated horticulturally in cooler areas. These include S. biflorus and S. uniflorus from New Zealand.
Text by A. Doust (1990); edited KL Wilson (Feb 2014; Sept 2015) Taxon concept:
Taxa not yet included in identification key
Scleranthus sp. Fitz's Hill (J.G.West 5342)
| Key to the species | |
1 | Calyx lobes erect, very much shorter than the calyx tube; stamen 1 | 2 |
| Calyx lobes more or less spreading, at least as long as the calyx tube; stamens 2–10 | 6 |
2 | Flowers solitary on scabrous peduncles; bracts 2 | Scleranthus singuliflorus |
| Flowers paired on glabrous or hairy peduncles; bracts 4 Back to 1 | 3 |
3 | Stems and bracts with some hairs; leaves in fascicles; plant usually prostrate, spreading, straggly and lax | 4 |
| Stems and bracts glabrous; leaves not in fascicles; plant usually cushion-like, dense, compact Back to 2 | 5 |
4 | Diaspore (fruit and surrounding persistent calyx) urceolate, i.e. with a well-defined 'neck' at the base of the sepal lobes, with strongly thickened longitudinal ribs; lobes incurved to apex | Scleranthus sp. Fitzs Hill (J.G.West 5342) |
| Diaspore ovate, i.e. lacking a well-defined neck, with obscure or narrow longitudinal ribs; lobes more or less straight, coming to a point at the apex Back to 3 | Scleranthus fasciculatus |
5 | Sepals 4; stamens level with or exserted beyond top of sepals, long-persistent | Scleranthus biflorus |
| Sepals 5; stamens shorter than sepals, shed early Back to 3 | Scleranthus brockiei |
6 | Flowers shortly pedicellate; calyx lobes linear, sometimes with narrow, scarious margins | 7 |
| Flowers not pedicellate; calyx lobes lanceolate, often with wide scarious margins Back to 1 | 8 |
7 | Leaves crowded together in pseudwhorls separated by internodes usually more than 8 mm long; stamens 5–10 | Scleranthus annuus |
| Leaves not crowded together, distributed evenly along the stem; stamens 2 Back to 6 | Scleranthus minusculus |
8 | Leaves pungent; calyx lobes pungent; flowers with 5 stamens and 5 linear staminodes | Scleranthus pungens |
| Leaves acute but not pungent; calyx lobes more or less acute; stamens 2 Back to 6 | Scleranthus diander |
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